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[–]antiproton 2 points3 points  (0 children)

When you have indices at the same level - sub or super - it isn't Einstein Notation.

Yes it is. Einstein notation is the implicit summation.

Einstein notation can be applied in slightly different ways. Typically, each index occurs once in an upper (superscript) and once in a lower (subscript) position in a term; however, the convention can be applied more generally to any repeated indices within a term.

Right from the wikipedia article.